Imagine, essentially, "Black Hawk Down" or perhaps "Saving Private Ryan" with all of Warlord Aidid's soldiers or the Nazi's replaced with invading extra terrestrials and you've got the gist of "Battle: Los Angeles." It's a top-to-bottom completely typical war film, just one involving aliens. If you can get behind that conceit, it's not bad at it what it does. If you can't, there's nothing else here for you.

In the early morning hours someday not far from now astronomers spot asteroids appearing out of nowhere and preparing to crash into the Earth. Except their not asteroids, they're delivery vehicles for an invading alien force beginning a combined conquest of the planet starting with the major costal cities like Tokyo, London, New York … and Los Angeles.

Which is about as much of a macro view of the plot of "Battle: Los Angeles" as you're going to get. Director Jonathan Liebesman ("The Texas Chainsaw Massacre: The Beginning:") has opted for an extremely targeted story, following just the actions of one company of the 25th Marine Battalion over the course of the first 24 hours of the invasion.

And as alien invasion stories go it's not a bad way to do one. Liebesman has jettisoned a lot of the deadweight that gets carried around in the kind of techno-thrillers alien invasion films normally turn into. There are no bureaucrats and politicians dealing with moral dilemmas over nuking cities, no courageous scientists whose initial warnings weren't heeded. Cinema verite is the order of the day; as Liebesman tries to recreate what it would actually be like to be a soldier in that sort of battle. Which as it turns out is like being soldier in most any other type of battle: bullets coming from nowhere, friends and comrades suddenly being killed.

Unfortunately, in the process of ditching all of those tropes, he's picked up a lot of typical war movie ones. Dealing with a cast of largely identical grunts, the film spends a very brief amount of time at the beginning trying to distinguish them using the standard war film soldier clichés. One soldier is getting ready to get married, one guy is good at hotwiring cars because he's from New Jersey, another young rookie soldier is more worried about losing his virginity than his eminent departure for combat, that sort of thing. On the one hand clichés become clichés for a reason. On the other hand there's also a reason the word has become a pejorative, too. It's shorthand for laziness; if you're not going to bother with characterization you might be better off literally not bothering.

Which is more or less the effect of the actual combat sequences once the Marines are sent into the heart of the city as part of a force sent to rescue captured civilians and evacuate them before the Air Force carpet bombs the city. Once the shooting begins Liebesman's choice of verisimilitude displays its wisdom as the characters revert to pure soldiers. They don't spend a lot of time in the middle of combat worrying about their girl back home or racing off to find their trapped sister. They're too busy securing hallways, rescuing buddies and checking their flanks as they advance down smoke strew streets. They're, you know, soldiers.

At their heart is Master Staff Sergeant Nantz (Aaron Eckhart), you're prototypical grizzled veteran who is done with combat and ready for retirement. He's suffering from his own PTSD as a result of losing several Marines during his last tour in Iraq and he's ready to move on. Naturally he's saddled with a completely green commanding officer (Ramón Rodríguez) after being sent to the Company at the last minute to replace a Staff Sergeant on leave. A Company that includes the brother of one of the Marines he lost, no less.

That said, for the most part "Battle: Los Angeles" doesn't dwell on that part of it, and most of when it does comes across in small moments (such as Nantz's delayed reaction to a particularly intense firefight with an alien UAV) that add together to make a whole character arc.

The rest of the time it's all about soldiers being soldiers, and being followed around with just shaky handicams everywhere they go. It's not trying to be a documentary but it is trying to ape the look of one so clear shots of what's going on are not the order of the day. The angles are low and swerve wildly like a Greengrass film on steroids, which certainly serves the feel Liebesman is going for but if you don't like watching movies like that then "Battle: Los Angeles" is not for you.

It also helps to keep the alien critters themselves mostly unseen, because when you do see them they don't always look great. The effects are serviceable but a lot of the CG budget seems to have been saved for the big finale when the remaining Marines stage an assault on the aliens Command and Control ship. Ultimately that choice also fits the style as well, as the film isn't about the aliens really and the only time they're encountered is when they're advancing with weapons drawn, which doesn't make for great drama but does replicate the feel of what the situation would really be like.

Unfortunately there are some civilians the Marines come across in a police station from whom Liebesman can't resist trying to draw a little bit of melodrama. Ordinarily that would be a good next step, but "Battle: Los Angeles" just isn't up to that. It can handle soldiers fighting aliens in a professional, believable manner, but real human interaction tends to come off as strained if not unintentionally funny. Part of that stems from Eckhart's extremely grim performance, which perfectly fits both his past and his situation (he is getting shot at after all), but is less suited to anything beyond battle.

"Battle: Los Angeles" is an entertaining if unimaginative war film, but anyone expecting anything else from it—including the filmmakers themselves—are barking up the wrong tree.